Gain in Definition 1 of 2Pro Tip 1/3Progressive Growth Usually implies gradual improvement in a skill or understanding over time. She continues to gain in proficiency with the software. Pro Tip 2/3Emotional Evolution Can indicate becoming stronger emotionally, like in confidence or independence. He gained in self-assurance as he spoke. Pro Tip 3/3Metaphoric Use Sometimes used metaphorically to express non-physical or intangible advancements. The team gained in unity after the retreat.